This invention relates to aircraft engine protection devices and, more particularly, to covers placed in front of the fan blades of aircraft engines so as to prevent the intrusion of foreign bodies. The present invention is directed to a device designed to prevent the intake of both large animals and foreign objects into the aircraft.
Protecting airplanes from damage due to birds or other airborne hazards has long been the goal of the prior art. While a direct strike on a fuselage is damaging to the airframe, the more pressing issue is when a bird strikes or other airborne hazard strikes the internal machinery of the engine assembly. Bird or foreign body strikes can cause catastrophic engine failure, resulting in loss of control of the airplane and possibly a forced or emergency landing. Currently, there is no effective device that both protects the engine while providing a non-lethal solution to prevent birds from entering the engine housing.
Problems caused by the injection of foreign objects into the inlet of engines has been previously known and recognized. For example U.S. Pat. Nos. 7,615,087; 4,833,879; 5,411,224; 3,426,981 and US App 2009/0101760, all discuss the danger of foreign bodies striking the engine intake and propose solutions. They are all hereby incorporated by reference. However, such devices and systems are known to limit engine thrust or create other problems with weight, maintenance, or cost. For example U.S. Published Application No. 2009/0101760 to Ghogomu provides for a protective screen designed to be mounted at the front of the intake of a jet engine nacelle. It is in the shape of a radial dome-shaped screen with interlocking wire mesh, rods and bars. While the Ghogomu prior art seeks to prevent foreign bodies from entering the engine intake, it does so in a manner that extends the profile of the engine, requires metal construction, and is capable of becoming a hazard itself if damaged.
Another example of failed design choices can be seen in U.S. Pat. No. 5,411,224 to Dearman et al. Dearman provides for a guard apparatus to be positioned in front of a jet engine intake that has a plurality of concentric rings of gradually decreasing diameter beginning at the cowl of the engine and descending in circumference towards a front end. Through this shape, Dearman also provides a conical cover to the engine cover. As in Ghogomu, the engine cover is formed of metal rods and bars formed into a structural mesh. While the device would clearly prevent foreign bodies from entering the engine intake, there are significant drawbacks. For instance, the profile of the guard apparatus extends beyond the cover of the engine such that the profile of the air plane has been changed. Additionally, the guard is formed of metal and could pose a significant foreign body risk if damaged.
It would therefore be of benefit to provide an engine intake cover that does not increase the physical dimensions of the aircraft. Furthermore, it would be of benefit to provide an aircraft engine intake cover that resisted entry of foreign bodies while decreasing possibility of engine damage if the cover should be breached or damaged.